1. Field of the Invention
This invention relates to a well intervention systems and methods of providing a control, chemical injection, and/or kill system for light well intervention, in general, and providing systems and methods which employ a remote connection point for control, chemical injection, and/or kill system umbilicals that is remote from the wellhead, in particular.
2. Description of the Related Art
Intervention in a subsea well may be required to provide repair, inspection/diagnostics, maintenance, on the well, to provide for improvements in order to increase production, or to and production. Light well intervention is generally considered to be defined, at least in part, as an intervention operation which does not need a drilling rig to provide access to the well.
A subsea well system such as a water injection well or a producing well does not normally have a drilling rig positioned above it or a riser assembly extending between the subsea well and drilling rig or other surface vessel that can provide a conduit for performing maintenance and/or intervention operations.
A typical water injection well includes a tubing spool assembly, a tubing hanger assembly, a water injection tree assembly landing atop and connected to the tubing spool assembly, a lower riser package landing atop and connected to the water injection tree assembly, an emergency disconnect package landing atop and connected to the water injection tree assembly, a riser stress joint landing atop and connected to the emergency disconnect package, a riser crossover landing atop and connected to the riser stress joint, and a pressure control head landing atop and connected to the riser crossover.
The normal procedure in subsea light well intervention for such type of well is to position a vessel of convenience, for example, a large supply boat (e.g., repair/inspection/maintenance vessel), or a specially designed light well intervention vessel or rig above the wellhead assembly. A wireline work tool, which can be a “dumb” tool or electric powered, is extended either through the moon pool of the vessel or over the side of the vessel typically via a crane-type device. The wireline tool connects to and extends through the pressure control head. The procedure also includes running electrical and/or hydraulic umbilicals and/or annulus umbilicals such as, for example, kill and chemical injection lines, from a heave compensating winch also located on the vessel adjacent the moon pool or crane location. These umbilicals are typically deployed by directly attaching them to the emergency disconnect package, which places them in close proximity of the wireline of the wireline tool. Guidelines are then utilized to separate the umbilicals from the wireline to prevent fouling or damage to the umbilicals. As such, this form of umbilical deployment system has been recognized by the inventors to be vulnerable and inefficient.
Accordingly, recognized by the inventors is the need for a system and methods for performing a light well intervention which can reduce congestion adjacent the moon pool/deployment location; which can maximize the distance between the umbilicals and the wireline to avoid damaging the umbilical and/or wireline, particularly in environments with high currents or offsets; which does not require the deployment and installation of guidelines to prevent umbilical entanglement; which can allow for smaller vessels to be used; and which can maximize its operating window of the vessel, thereby also reducing the cost of the intervention.
Also recognized is the need for a system and method for performing a light well intervention which does not require a heave compensation capability on the umbilical winch; which allows the umbilicals to be deployed sufficiently far from the vessel's hull so that in adverse weather conditions the umbilicals can be prevented from being damaged as a result of contacting the hull; and which allows for easy reconnection of the control lines to reestablish surface control in the event of an emergency disconnect and/or third-party access in the event of a lost vessel.